EXHIBIT 25

SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

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STATEMENT OF ELIGIBILITY UNDER THE
TRUST INDENTURE ACT OF 1939 OF A
CORPORATION DESIGNATED TO ACT AS TRUSTEE

Check if an Application to Determine Eligibility
of a Trustee Pursuant to Section 305(b)(2) __

STATE STREET BANK AND TRUST COMPANY
(Exact name of trustee as specified in its charter)

Massachusetts 04-1867445
(Jurisdiction of incorporation or (I.R.S. Employer
organization if not a U.S. national bank) Identification No.)

225 Franklin Street, Boston, Massachusetts 02110
(Address of principal executive offices) (Zip Code)

John R. Towers, Esq. Senior Vice President and Corporate Secretary
225 Franklin Street, Boston, Massachusetts 02110
(617)654-3253
(Name, address and telephone number of agent for service)

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CABOT CORPORATION
(Exact name of obligor as specified in its charter)

DELAWARE 04-2271897
(State or other jurisdiction of (I.R.S. Employer
incorporation or organization) Identification No.)

75 STATE STREET
BOSTON, MA 02109
(Address of principal executive offices) (Zip Code)

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CABOT CORPORATION SERIES A MEDIUM - TERM NOTES
(Title of indenture securities)

GENERAL

ITEM 1. GENERAL INFORMATION.

FURNISH THE FOLLOWING INFORMATION AS TO THE TRUSTEE:

(a) NAME AND ADDRESS OF EACH EXAMINING OR SUPERVISORY AUTHORITY TO
WHICH IT IS SUBJECT.

Department of Banking and Insurance of The Commonwealth of
Massachusetts, 100 Cambridge Street, Boston, Massachusetts.

Board of Governors of the Federal Reserve System, Washington,
D.C., Federal Deposit Insurance Corporation, Washington, D.C.

ITEM 2. AFFILIATIONS WITH OBLIGOR.

IF THE OBLIGOR IS AN AFFILIATE OF THE TRUSTEE, DESCRIBE EACH SUCH
AFFILIATION.

The obligor is not an affiliate of the trustee or of its
parent, State Street Boston Corporation.

(See note on page 6.)

ITEM 3. THROUGH ITEM 15. NOT APPLICABLE.

ITEM 16. LIST OF EXHIBITS.

LIST BELOW ALL EXHIBITS FILED AS PART OF THIS STATEMENT OF ELIGIBILITY.

1. A COPY OF THE ARTICLES OF ASSOCIATION OF THE TRUSTEE AS NOW IN
EFFECT.

A copy of the Articles of Association of the trustee, as now
in effect, is on file with the Securities and Exchange
Commission as Exhibit 1 to Amendment No. 1 to the Statement of
Eligibility and Qualification of Trustee (Form T-1) filed with
the Registration Statement of Morse Shoe, Inc. (File No.
22-17940) and is incorporated herein by reference thereto.

2. A COPY OF THE CERTIFICATE OF AUTHORITY OF THE TRUSTEE TO COMMENCE
BUSINESS, IF NOT CONTAINED IN THE ARTICLES OF ASSOCIATION.

A copy of a Statement from the Commissioner of Banks of
Massachusetts that no certificate of authority for the trustee
to commence business was necessary or issued is on file with
the Securities and Exchange Commission as Exhibit 2 to
Amendment No. 1 to the Statement of Eligibility and
Qualification of Trustee (Form T-1) filed with the
Registration Statement of Morse Shoe, Inc. (File No. 22-17940)
and is incorporated herein by reference thereto.

3. A COPY OF THE AUTHORIZATION OF THE TRUSTEE TO EXERCISE CORPORATE
TRUST POWERS, IF SUCH AUTHORIZATION IS NOT CONTAINED IN THE DOCUMENTS
SPECIFIED IN PARAGRAPH (1) OR (2), ABOVE.

A copy of the authorization of the trustee to exercise
corporate trust powers is on file with the Securities and
Exchange Commission as Exhibit 3 to Amendment No. 1 to the
Statement of Eligibility and Qualification of Trustee (Form
T-1) filed with the Registration Statement of Morse Shoe, Inc.
(File No. 22- 17940) and is incorporated herein by reference
thereto.

4. A COPY OF THE EXISTING BY-LAWS OF THE TRUSTEE, OR INSTRUMENTS
CORRESPONDING THERETO.

A copy of the by-laws of the trustee, as now in effect, is on
file with the Securities and Exchange Commission as Exhibit 4
to the Statement of Eligibility and Qualification of Trustee
(Form T-1) filed with the Registration Statement of Eastern
Edison Company (File No. 33-37823) and is incorporated herein
by reference thereto.

5. A COPY OF EACH INDENTURE REFERRED TO IN ITEM 4. IF THE OBLIGOR IS
IN DEFAULT.

Not applicable.

6. THE CONSENTS OF UNITED STATES INSTITUTIONAL TRUSTEES REQUIRED BY
SECTION 321(b) OF THE ACT.

The consent of the trustee required by Section 321(b) of the
Act is annexed hereto as Exhibit 6 and made a part hereof.

7. A COPY OF THE LATEST REPORT OF CONDITION OF THE TRUSTEE PUBLISHED
PURSUANT TO LAW OR THE REQUIREMENTS OF ITS SUPERVISING OR EXAMINING
AUTHORITY.

A copy of the latest report of condition of the trustee
published pursuant to law or the requirements of its
supervising or examining authority is annexed hereto as
Exhibit 7 and made a part hereof.

NOTES

In answering any item of this Statement of Eligibility and
Qualification which relates to matters peculiarly within the knowledge of the
obligor or any underwriter for the obligor, the trustee has relied upon
information furnished to it by the obligor and the underwriters, and the trustee
disclaims responsibility for the accuracy or completeness of such information.

The answer furnished to Item 2. of this statement will be amended, if
necessary, to reflect any facts which differ from those stated and which would
have been required to be stated if known at the date hereof.

SIGNATURE

Pursuant to the requirements of the Trust Indenture Act of 1939, as
amended, the trustee, State Street Bank and Trust Company, a corporation
organized and existing under the laws of The Commonwealth of Massachusetts, has
duly caused this statement of eligibility and qualification to be signed on its
behalf by the undersigned, thereunto duly authorized, all in the City of Boston
and The Commonwealth of Massachusetts, on the 29TH DAY OF JANUARY, 1997.

STATE STREET BANK AND TRUST COMPANY

By /s/ Henry W. Seemore
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HENRY W. SEEMORE
ASSISTANT VICE PRESIDENT

2
4

EXHIBIT 6

CONSENT OF THE TRUSTEE

Pursuant to the requirements of Section 321(b) of the Trust Indenture
Act of 1939, as amended, in connection with the proposed issuance by CABOT
CORPORATION of its CABOT CORPORATION SERIES A MEDIUM - TERM NOTES, we hereby
consent that reports of examination by Federal, State, Territorial or District
authorities may be furnished by such authorities to the Securities and Exchange
Commission upon request therefor.

STATE STREET BANK AND TRUST COMPANY

By: /s/ Henry W. Seemore
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HENRY W. SEEMORE
ASSISTANT VICE PRESIDENT

DATED: JANUARY 29, 1997

EXHIBIT 7

Consolidated Report of Condition of State Street Bank and Trust Company of
Boston, Massachusetts and foreign and domestic subsidiaries, a state banking
institution organized and operating under the banking laws of this commonwealth
and a member of the Federal Reserve System, at the close of business December
31, 1995, published in accordance with a call made by the Federal Reserve Bank
of this District pursuant to the provisions of the Federal Reserve Act and in
accordance with a call made by the Commissioner of Banks under General Laws,
Chapter 172, Section 22(a).

Thousands of
ASSETS Dollars

Cash and balances due from depository institutions:
Noninterest-bearing balances and currency and coin .... 1,331,827
Interest-bearing balances ............................. 5,971,326
Securities ..................................................... 6,325,054
Federal funds sold and securities purchased
under agreements to resell in domestic offices
of the bank and its Edge subsidiary ................... 5,436,994
Loans and lease financing receivables:
Loans and leases, net of unearned income ....4,308,339
Allowance for loan and lease losses ......... 63,491
Loans and leases, net of unearned income and allowances 4,244,848
Assets held in trading accounts ................................ 1,042,846
Premises and fixed assets ...................................... 374,362
Other real estate owned ........................................ 3,223
Investments in unconsolidated subsidiaries ..................... 31,624
Customers' liability to this bank on acceptances outstanding ... 57,472
Intangible assets .............................................. 68,384
Other assets ................................................... 670,058

Total assets ................................................... 25,558,018
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LIABILITIES

Deposits:
In domestic offices ................................... 6,880,231
Noninterest-bearing ................4,728,115
Interest-bearing ...................2,152,116
In foreign offices and Edge subsidiary ................ 9,607,427
Noninterest-bearing ................ 28,265
Interest-bearing ...................9,579,162
Federal funds purchased and securities sold under
agreements to repurchase in domestic offices of
the bank and of its Edge subsidiary ................... 5,913,969
Demand notes issued to the U.S. Treasury and Trading Liabilities 530,406
Other borrowed money ........................................... 493,191
Bank's liability on acceptances executed and outstanding ....... 57,387
Other liabilities .............................................. 620,287
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Total liabilities .............................................. 24,102,898
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EQUITY CAPITAL
Common stock ................................................... 29,176
Surplus ........................................................ 228,448
Undivided profits .............................................. 1,197,496
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Total equity capital ........................................... 1,455,120
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Total liabilities and equity capital ........................... 25,558,018
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I, Rex S. Schuette, Senior Vice President and Comptroller of the above named
bank do hereby declare that this Report of Condition has been prepared in
conformance with the instructions issued by the Board of Governors of the
Federal Reserve System and is true to the best of my knowledge and belief.

Rex S. Schuette

We, the undersigned directors, attest to the correctness of this Report of
Condition and declare that it has been examined by us and to the best of our
knowledge and belief has been prepared in conformance with the instructions
issued by the Board of Governors of the Federal Reserve System and is true and
correct.

David A. Spina
Marshall N. Carter
Charles F. Kaye